Preheater to sealing machine transfer device



2,821,810 PREHEATER TO SEALING MACHINE TRANSFER DEVICE I Filed D80. 15, 1955 J. E. BULLERS E! AL- Feb. 4, 1958 4 Sheets-Sheet 1 JOHN E. BULLERS AIYD CHAUNCEY L. MOSES INVENTORS ATTORNW Feb. 4, 1958 PREHEATER TO SEALING MACHINE TRANSFER DEVICE Filed Dec. 16, 1955 4 Sheet-sSheet 2 INVENTORS JOHN E. BULLERS AND CHAUNCEY L. MOSES Feb. 4, 1958 f J. E. BULLERS ET AL 2,821,810

PREHEATER -TO SEALING MACHINE TRANSFER DEVICE Filed Dec. 1a, 1955 x 4 Sheets-Sheet s TIE-T4 INVENTORS JOHN E. BULLERS ANBDY CHAUNCEY L. MOSES ATTORN Feb. 4, 1958 J. E. BULLERS ET- AL 2,821,810

\ APREHEATER TO SEALING MACHINE TRANSFER DEVICE Filed D90. 16. 1955 4 Sheets-Sheet 4 INVENTORS JOHN E. BULLERS AND CHAUNCEY moses ATTORNEY PREHEATER T SEALING MACHINE TRANSFER DEVICE John E. Bullers, Altoona, and Chauncey L. Moses, Duncansville, Pa., assignors to Sylvania Electric Products Inc., a corporation of Massachusetts Application December 16, 1955, Serial No. 553,647

4 Claims. (Cl. 49-2) This invention relates to mechanism for transferring electron tube assemblies from a preheater to the peg of a sealing machine and for adjusting parts of such an assembly with respect to one another.

In one method of manufacture of electron tubes, assemblies consisting on the one hand of bulbs with attached exhaust tubulation and on the other hand of stems with mounts afiixed thereto are preheated in a long chamber provided with electric heaters, the assemblies being carried on a conveyor traversing the chamber. The bulbs are telescopcd over the mounts but are spaced from the stem to allow hot gases to pass freely through the exhaust tubulation, through the interior of the bulb and out between the bulb and stem. The mechanism for preheating the assemblies is positioned close to an indexing turret provided with pegs to carry the assemblies around past mechanisms which seal the bulb to the stem. To effect this result it is necessary to preliminarily thrust the bulb down over the mount and to a position where the bottom of the bulb is opposite the stem.

It is an object of the present invention to provide a means for automatically transferring a preheated bulb and stem-mount assembly from a preheater to a peg on the sealing machine.

It is a further object of the invention to provide thrust mechanism operated from the transfer means to push the bulb over the mount into proper sealing position with respect to the stem.

It is a further object of the invention to make the transfer and thrust mechanisms of few and rugged parts to provide for trouble free operation.

These and other objects will become apparent after reading the following specification and claims in conjunction with the accompanying drawing in which Fig. 1 is a perspective view of the new transfer and pusher mechanism showing its relationship to the sealing pegs of a bulb to stem sealing machine, with parts in section.

Fig. 2 is a front view of the transfer and pusher mechanism, parts being shown in section.

Fig. 3 is a fragmental sectional view of a motor for lifting certain parts in the mechanism and its connections.

Fig. 4 is an elevation of the mechanism, partly in section, taken at right angles to the view shown in Fig. 2.

Fig. 5 is a plan view of the mechanism, parts being broken away and in section to expose hidden portions and Fig. 6 is a cross section on the line 66 of Fig. 5.

I Referring to the drawings in greater detail at 10 there is disclosed an endless link chain conveyor mounting equally spaced resilient clasps 12 which releasably retain the exhaust tubulations of tubulated bulbs. This chain traverses a preheater chamber '14 of known construction of which only the end portion is shown and is loaded by an operator at the other end of the run of the chain. The chain is indexed in synchronism with the indexing of a receiving mechanism here illustrated as a turret 16 of a sealing machine, which turret carries equally spaced pegs States Patent 18. The chain passes around an end sprocket 20 sup ported by a channel bar 22 running substantially the length of a run of the chain.

Supported by the sides of the channel bar is a pair of side panels 24 and 26. The side panels are adjustably fixed longitudinally of the bar by means of plate ribs 28 on the sides of the channel bar fitting in grooves 30 of the panels 2 and 26 and by reason of bolts 32 passing through slots 34 in the panels and threaded into the channel bar. The panels are further held spaced apart by an intermediate plate 36 suitably fastened within grooves in the panels 24 and 26 and by a base plate 38 also suitably fastened in grooves in the side panels as by bolts 40. The space between the under face of the web of the channel bar 22 and the upper face of the intermediate plate 36 affords space for the lower run of the chain conveyor, stripped of its assemblies. Between the intermediate plate and the base plate there is movable the mechanism for transferring an assembly from the conveyor onto a peg of the sealer and part of the mechanism for pushing the bulb 41 futher down on the mount 43 toward the stem 45. The structure is further reinforced by a rear cover plate 42 fastened to the side panels and to the intermediate and base plates, the rear plate extending upwardly only to the level of the intermediate plate 36 to allow space for travel of the lower run of the chain.

Spanning the space between the plates 36 and 38 is a pair of guide rods 44 having reduced ends 46 lodged in holes 48 in the plates. Slidably mounted on these rods is a platform 5% having an offset portion 52 forming a jaw housing, the housing being provided with a cover plate 54 bolted to the housing. To facilitate sliding action of the platform on the bars, the platform is provided with bronze bushings 56, held in place by conventional means, as by a collar 58 fastened to the bushing and butting against an enlargement 60 on the platform or carriage, the bushing also being enlarged at its upper end to engage the enlargement. To reciprocate the platform or carriage there is provided a double ended fluid motor 62 of which the top cap 64 is provided with an externally threaded neck 66 extending through an opening in the base plate 38 and fastened to the plate by a nut 68. The inlet and exhaust conduits 76 to the cylinder of the motor are connected to valves (not shown) under control of the indexing movement of the sealer. The upper end of the piston rod 72 of the motor is threaded into the platform 50 midway between the guide rods 44, a lock nut 74 being provided to prevent undesired separation of parts. The downward movement of travel of the carriage is limited by any suitable means, as by the limit of travel of the piston in the fluid motor 62.

The platform, as will be seen in Fig. 4, to the right of the guide rods, is at a slightly lower elevation than the portion to the left of the rods and provides a seat for a horizontal motor 76 which may be an electromagnetic motor but is preferably an air motor. The motor is fastened to the platform by bolts 77 and has a piston 78 and piston rod 86. The rod 80 passes through a bearing 82 forming part of the cover plate 84 of the motor which plate is fastened to ears 86 on the cylinder by screws 88. The piston rod is threaded into a cam bar and secured thereto by a set screw 92. The piston 78 is urged to the left in Fig. 5 and to the right in Fig. 4, by a spring 94 reacting between the cover plate of the motor and a metallic washer 96 bearing against the piston 78. A conduit 98 leads motive fluid, such as air, under control of indexing movement of the sealer, to the rear of the piston through a suitable fitting 1%. The rear cover plate 42 of the transfer mechanism is suitably slotted as indicated at 102 in Fig. 2 to permit movement of the motor fluid lead-ins as the platform 56 moves up and down. The bar 90 at its free end tapers to an edge and provides two cam surfaces 104 operative on the rear portions of jaw arms or levers 106 pivoted on a press fit pin 108 on the offset portion 52. Each of these levers'has an antifriction roller 110 at one of its ends to be engaged by the cam surface 104 and an exhaust tube engaging jaw 112 at the other end, with the jaws extending beyond the edge of the platform. The jaws are elongated in the direction of the tubulation to be grasped to form vertical grasping faces and are normally kept separated by coil springs 114 each having an end seated in a recess in an arm 106 and each having the other end seated in a recess in a block 116 fastened to the offset jaw housing 52. In Figures 1 and 5, the jaws 112 are shown as having been advanced toward each other against the action of the springs by reason of projection of bar 90 between the rear ends of the jaw levers. Upon application of fluid pressure to the motor 76,the jaws 112 will be forced together. Upon release of pressure the spring 94 will retract the cam bar 90 and the springs 114 will separate the jaws. In operation, parts are so timed that when the platform 50 is elevated and the jaws separated, the conveyor will be indexed to orientate a tubulation of an electron assembly between the jaws and opposite the long grooves in the jaws. The jaws thereupon close on the tubulation and the platform moves downwardly to thrust the assembly onto a peg on the sealer which in the meantime has indexed to a position directly below the tube assembly. In the process of moving down, the jaws withdraw the tubulation from the resilient clasps on the chain conveyor. The tube and stem are lowered a suificient distance to allow them to come to rest on the peg without moving the bulb down to its final position relative to the stem. The jaws are permitted to open only after the platform has reached its lower position.

Fastened to the underside of the platform 50 as by screws 118 is a press rod carrier 120, the rod extending laterally beyond a cut away edge 122 of side panel 24. Mounted on this side panel in outboard fashion, as by fasteners 124, is a bracket 126 providing spaced slide bearings for a press rod 128 fastened at its lower end as by set screw 130 to the carrier and fastened by set screw 131 at its upper end to a two part arm 132, made extensible by means of conventional bolt and slot connection. At the free end of the arm there is provided a bearing in which a press spring cylinder or housing 134 is adjustably positioned as by a set screw 136. Telescoped within this cylinder is the shaft 138 of a press bearing housing 140 within which is a roller bearing 142 in the inner race of which is a holder 144 for a press pad 146 of suitable yielding material such as vulcanized fiber or leather. The shaft 138 is provided with a cross pin 148 riding in slots 150 formed in the walls of the cylinder 134, and reacting between the top of the shaft and the cylinder 134 is :a spring 152. The cylinder 134 is positioned so as to be directly over a peg 18 on the sealer when it is indexed to the next position from that at which it receives a tube assembly from the transfer jaws.

On the downward motion of the platform to insert a tube assembly onto a peg, the press assembly comprising parts 120, 128, 132, 134, 140, and 146 also move down, so that the press pad engages the top of a tubulation of a tube assembly positioned on the underneath peg and forces the tubulation and attached bulb down over the mount so that the bottom of the bulb is located opposite to the stem wafer for proper sealing thereto, during subsequent operation of the sealer. The pad is limited in the downward motion by engagement of the cross pin 148 with the walls.

4 at the lower ends of slots at which time the bulb had been shifted relative to the stem so that the lower end of the bulb is opposite the stem to allow for subsequent proper sealing of bulb to stem.

Having thus described the invention, what is claimed is:

1. In tube assembly handling apparatus, wherein there is an indexible mechanism for receiving a tube assembly comprised of a tubulated bulb and stem with its mount and wherein the bulb and mount are frictionally held together and in such position that the bottom of the bulb is vertically spaced from the stem and wherein said receiving mechanism has equally spaced pegs, a. transfer device operative to sequentially supply the pegs with said tube assemblies, means to feed the transfer device with said tube assemblies, and means movable by and with the transfer device for moving the bulb further down over the mount to a position such that the bottom of the bulb is opposite the stem for easy sealing thereto.

2. In tube assembly handling mechanism, a support, a vertically reciprocating platform mounted in the support, a pair of opposed jaws with vertical grasping faces pivotally mounted on said platform, with the jaws positioned beyond an edge of the platform, means on said platform for operating said jaws, a rod having fixed connection with said platform vertically slidable in hearings on said support, a vertically movable press device connected with said rod and movable therewith, said mechanism being adapted by means of the jaws to move a tubulated bulb and stemmount assembly onto an indexable peg of a sealing machine and :said press device being adapted to engage the end of the tubulation and .force the tubulation and bulb downwardly with reference to the stern mount.

3. In a tube assembly handling mechanism, a support, a reciprocatable platform mounted for movement in said support, a pair of opposed jaws with vertical grasping faces movably mounted on said platform, with the jaws positioned beyond an edge of said platform, means on said platform for operating the jaws to normally maintain them separated, means on said platform to close the jaws when the platform is elevated and to permit the jaws to open only after the platform has reached a lower position, a rod movable with said platform and vertically slidable in hearings on said support, a vertically movable press device connected with said rod and movable therewith, said mechanism being adapted by means of the jaws to move a tubulated bulb and stem-mount assembly onto an indexable peg of .a sealing machine and said press device being adapted toengage the end of the tubulation and force the tube and bulb downwardly with reference to 'the stem mount.

4. In a tubeassernb'ly handling mechanism, a support, a vertically reciprocatable platform mounted in said support, a pair of opposed jaws mounted on the platform for movement toward and from each other, means on said platform for operating said jaws, means for vertically reciprocating the platform, a rod slidably mounted on the support and fixedly connected for movement with the platform, an arm afiixed to the upper end of the rod, a spring containing housing fixed to the otherwise free end of said arm, a shaft telescoped in said housing and under influence of the spring, and 'a horizontal article engaging surface on the lower end of the shaft.

References Cited in the file of this patent UNITED STATES PATENTS 1,742,153 Stiles et al Dec. 31, 1929 1,813,565 Conn July 7, 1931 1,969,511 Heere et al Aug. 7, 1934 2,098,030 Donovan et a1. Nov. 2, 1937 

